甲基丙烯酰氧乙基三甲基氯化铵和丙烯酰胺的反相乳液聚合

以甲基丙烯酰氧乙基三甲基氯化铵(DMC)和丙烯酰胺(AM)为原料,通过反相乳液聚合技术,合成阳离子高分子聚合物.讨论了引发剂种类、乳化剂种类、单体浓度及配比、油水体积比等因素对共聚产物的特性黏度和体系稳定性能的影响,确定了最佳反应条件.在单体物质的量比为6∶3,油水体积比为1.3∶1,引发剂为氧化-还原引发剂或高效水溶性引发剂的条件下,得到产品.并对产物进行了絮凝实验以及红外光谱分析.     

聚牛磺酸丙烯酰胺的合成及表征

以牛磺酸丙烯酰胺为原料采用水溶液聚合法合成聚牛磺酸丙烯酰胺。采用L9(3)4正交设计法考察单体浓度,引发剂用量,反应时间,反应温度对产物黏度的影响,确定聚牛磺酸丙烯酰胺的最佳合成条件为单体浓度为20%,引发剂用量为0.4%,反应时间为6h,反应温度为50℃。并利用红外光谱、核磁共振氢谱对产物结构进行表征。     

分散聚合法制备单分散聚丙烯酰胺微球——反应动力学、分子量研究

本文采用聚乙烯基吡咯烷酮(PVP)为分散剂,偶氮二异丁腈(AIBN)为引发剂,在乙酸乙酯/乙醇(Ethyl acetate/Ethanol)的混合溶液中通过分散聚合法合成了单分散亚微米级的聚丙烯酰胺(PAM)微球,研究反应时间、混合溶液比例、分散剂浓度、初始单体浓度和引发剂浓度对聚合物分子量、聚合反应动力学的影响.     

制备亚微米级镍粉的意义

实验中采用了液相还原法,用六水硫酸镍作为原料,以水合肼作为还原剂,以三乙醇胺为有机保护剂,以CuS04作为成核剂,以NaOH调节溶液的PH值,研究了有机物含量、NaOH含量、反应温度时镍粉粒径及形貌的影响.实验中制备出的镍粉平均拉径为30～80nm,实验表明随着NaOH的量的增加,颗粒平均粒径将逐渐变小;NaOH/Ni2+增大,颗粒平均粒径将逐渐变小,若比例过大,反应剧烈而难以控制;随着反应温度提高,镍粉的颗粒也变小,但温度过高时水合肼挥发;随着(C2H50)3N/Ni2+的增加,镍粉的粒径将逐渐减小;亚微米级镍粉制备的电极的方阻比微米级制备的电极的方阻要小一些,在作为多层片式PTCR用内电极时具有更佳的效果.     

二甲基二烯丙基氯化铵-丙烯酰胺反相乳液聚合制备阳离子絮凝剂

本文以二甲基二烯丙基氯化铵(DMDAAC)和丙烯酰胺(AM)为单体,Span-60和Tween-80为复合乳化剂,二甲苯为连续相,采用反相乳液聚合方法,在氧化还原引发体系下,制备了AM/DMDAAC阳离子型共聚物P(AM-DMDAAC).结果表明,在35℃下,运用HLB值法得出复合乳化剂HLB值在5～8时,能形成稳定可聚合的乳液体系.从反相乳液聚合的机理出发,优化反应条件,阳离子度质量分数为33%的共聚物特性粘数可达0.89 L/g.     

技术转让与合作 高分子化工

加碱大块均聚后水解工艺 合成超高分子量聚丙烯酰胺 本项目采用加碱大块均聚后水解工艺,合成超高分子量聚丙烯酰胺产品。与国内外现行工艺(如薄片聚合工艺、加碱聚合同时水解工艺及AM单体均聚后加碱水解工艺)相比,该工艺具有产品分子量高,工艺简单可靠,工程放大因素小的特点,并已申请国家发明专利。 本项目发明的水溶性高效引发剂具有创新性。该引发剂可在较低温度下实现单体引发,链转移常数小,可用于丙     

镁、镁铝溶胶及其粉末的合成

分别以氯化镁、硝酸铝为镁、铝源,柠檬酸为稳定剂,采用溶胶凝胶过程制备出了稳定的镁、镁铝溶胶,并对煅烧后的样品进行了晶相和形貌分析。分析了氯化镁与柠檬酸的物质的量比、温度、保温时间对镁溶胶形成的影响,确定了氯化镁与柠檬酸的物质的量比3:1、100℃及恒温反应1h是生成镁溶胶较优的工艺参数。XRD分析结果表明镁凝胶粉末经800℃煅烧2h后,样品为立方氧化镁晶相,镁铝凝胶粉末经1200℃煅烧2h后,样品由立方尖晶石结构构成。由于高温煅烧引起了粉末团聚,SEM显示所得粉末为无规则形态。     

apg参与下vtes-丙烯酸酯共聚乳液的研究

以聚丙烯酸丁酯为种子乳液,在烷基糖苷(apg)的参与下将乙烯基三乙氧基硅烷(vtes)与丙烯酸酯进行乳液共聚,制成了聚合稳定性良好、性能稳定的有机硅丙烯酸酯共聚乳液.详细讨论了vtes用量对聚合过程稳定性和乳液粒径大小及分布的影响,结果表明:随着vtes用量的增加,乳液聚合的稳定性变差、乳胶粒的平均粒径增大、乳胶膜的吸水率减小.     

采用溅射高温分解法由氯化铜溶液制备CuO研究（韩国）

Hoseo大学的研究人员采用溅射高温分解法使用CuCl2溶液作为原料制得了粒子尺寸小于1um且具有单一粒径分布的精细氧化铜粉末，研究了反应温度、溶液和空气的喷射速度、喷嘴口的尺寸，原料溶液的浓度等因素对制得粉末性能的影响，所得粉末的结构随反应温度的增大而趋于紧密，而与原料溶液中铜的浓度无关，原料溶液中铜的浓度为30g/l时，所得粉末的粒子尺寸随反应温度的升高而增大。随着原料溶液铜浓度的增大，粉末的粒子尺寸相应增大而粉末表面趋于多孔状结构，当原料溶液中铜的浓度大于100g/l时，所得产物均为CuCl粉末，且与反应温度无关，当原料溶液中铜的浓度小于30g/l，且反应温度高于900摄氏度时，所得产物主要是CuO，随溶液喷射速度的增大，粉末的表面趋于多孔化，随喷嘴口尺寸的增大，粉末的粒子尺寸有所增大，且粉末表面呈现相当严重的混乱状态，随喷嘴处空气压力的增加，所得粉末粒子尺寸变小，且粒子尺寸的分布更为均匀。     

汽车工业滤纸浸渍乳液的研制

作者介绍了一种汽车工业滤纸浸渍乳液的制备方法.以丙烯酸丁酯、苯乙烯、甲基丙烯酸、硅烷偶联剂和交联型功能单体为主要原料,采用单体预乳化乳液聚合工艺,合成了滤纸浸渍乳液.讨论了单体的选择及配比、硅烷偶联剂、乳化剂对乳液性能的影响.结果表明:软硬单体丙烯酸丁酯与苯乙烯的最佳配比为(0.35～0.47):1;硅烷偶联剂和乳化剂的最佳用量分别为总单体量的0.68%～0.93%、0.45%.制得的乳液粒径细腻、固含量高、黏度适中、稳定性好、综合性能优异.     

Brown＇s Blossom in Britain-China

The overall strategic relationship between U.K. and China is ＂better than ever＂, China- Britain relations have maintained good momentum, with increased high-level exchanges and the reinforcement of strategic mutual trust, with more room for growth in the future.     

Challenge and Opportunity Go Hand in Hand——What Global Economic Agitation Brings to the China's Economy?

Domino effects of the global finance agitation As the origin of the subprime crisis,US financial institutions lost USS45 billion last year,accounted for over half of the total US,EU & Japan loss.Since January 15th,Chtigroup released its financial statement of the 4th quarter,showing a net deficit of USS9.83 billion,which marked the hisoric high of its quarterly deficit.     

Jean-Pierre Duprieu： Willing to Be A Legate of Sino-French Business

Estaing, former French president, Valery Giscard d＇Estaing attended Sino-French Economic Seminar held in Shanghai in early April and said that the world center has shifted from the west to the east with many European and US companies entering into Asia, and China has the ability to play an important role in the world stage. Estaing, naming himself＂French Confucian＂, then said in Chinese that a cook-group includes 10 people in ancient Chinese soldier system and the cook is in charge of cooking for them. And people who belong to the same cook are actually ＂Partners＂.     

China''''s Stock Market Wave

The annual meeting of the World Economy Forum was held in Davos,a little town in Switzerland,on January 23rd to the 27th this year,with the theme"the Power fo Collaborative Innovation",over 2500 celebrates from ture political and cconomic circles of more than 80 countries and challengred logether to talk about the future of the global economy in 2008,A Forum for the problems and challenges that face whole world,some of the keywords which drew attention during the event were:the U.S.subprime mortgage crisis,soaring energy prices,the economic slowdown in the U.S.ermerging economic bodies,authority funds and the general unpredictable nature of the global economy.     

Trade Promotion from Neighborhood

If you are considering to trade with companies in Japan or expanding your .business to Japan, we are ready to help from the very beginning.＂ You will find this greeting at the first sight on the Chinese website of Japan External Trade Organization （JETRO）. JETRO has committed itself in delivering highly efficient and quality services to meet the demand of internal and external customs including Japanese companies, hence winning a good reputation in the international trade arena. In recent years, with its priority in advancing business cooperation in South and East Asia, JETRO has made great achievement in promoting trade between China and Japan. Therefore, China＇s Foreign Trade interviewed Mr. Yoichi Maine, Deputy Director General of JETRO BEIJING.     

Auto Parts Market Potential Coming into Surface

Looking at the increasingly fierce competition in the world auto market. global automobile manufacturing industry, taking Europe, the U.S. and Japan as representatives, is gradually forming a new type of relationship, mutual cooperation between whole vehicle and parts manufacturers. We can clearly see that auto parts manufacturers have become independent from the whole vehicle manufacturing companies, which means that the former structure of auto industry has greatly changed, and a new relationship,     

Sinosteel：Extraordinary Moves in Industry Chess

Among the Fortune 500 firms,more and more images from China emerge out.On the 2008 list,Sinosteel Corporation,a landmark group of China industries quietly squeezes into the candidate line.As the largest steel service ＆ trade enterprise,its sales reached at RMB 111.24 billion,with a year-on-year increase of 83.03 percent,and the profit grew by 180.03 percent.On the Sinosteel 2008 Work Meeting,the president Huang Tianwen uttered,＂In the coming year,we will work for US$20 billion sales,and look forward to getting a position in Fortune 500 firms for ourselves.＂     

Walk Through Unusual Five Years—— An Exhibitor＇s Canton Fair Course

When the 103rd Canton Fair is approaching, an old friend of Canton Fair, Li Ying from Jiangsu prov-ince recollected his past five years＇ experiences to the grand trade meeting. Each year is special, with some unforgettable memories colored by the year.     

Domino Effect on Electricity and Coal Prices

In the middle of last December, the key purchase contracts for coal used in power generation in 2008 were signed, reflecting a demand for more than 1.085 billion tons. It is important to note that the country＇s five biggest power producers, China Huaneng Group, China Guodian Corporation, China Power Investment Corporation, China Huadian Corporation and China Datang Corporation, had settled on the prices on their purchase contracts, and they are expected to consume 290 million tons of coal for generating electricity,     

Slimmed May Day Holiday

Last November the State Council of China decided to renew its holiday system by reducing the seven-day May Day holiday to three days and introducing three new one-day public holidays, namely the Qingming Festival, Dragon Boat Festival and Moon Festival. By doing so, the three golden-week holidays that were introduced in 1999, namely the Spring Festival, May Day and National Day, could be better distributed.